This invention relates to radiants used in vented or unvented gas heaters and more particularly to such a radiant that is formed from an improved material whereby the radiant is more resilient and gives off increased amounts of radiant heat.
Heretofore, conventional radiants have been formed from a refractory clay material consisting essentially of kaolin and talc. The production of such radiants requires the performance of a number of difficult and time-consuming steps. First, the kaolin-talc composition is mixed with lubricants, binders, plasticizers and organic burnout materials, such as sawdust, to form a wetted mix which is granulated into small nodules which are pressed in dies to form one-half of the clay radiant. Two halves of the radiant are then cemented together to form a complete radiant. Such radiants are then dried and fired to develop good thermal shock resistance which results in a product which is extremely rigid and brittle. This results from the inherent low strength of the kaolin-talc composition and the great number of voids formed within the clay radiant due to the burned out organic materials which are added to reduce the weight and mass of the clay radiant so that the radiant will heat up quickly and glow to thus radiate heat into the area to be heated. While such radiants are light in weight, they are very susceptible to breakage, thus requiring the use of a multiple number of narrow width radiants with each conventional heater. In actual practice I have found as much as ten percent (10%) or more breakage of clay radiants in shipment to customers which results in high replacement costs and bad customer relations.
Also, cone-shaped projections have been provided on clay radiants in position to contact the gas stream to provide high levels of heat shortly after the burner is lit. Such cone-shaped projections are frequently broken off or unformed during manufacture, thus significantly reducing the potential radiant energy.